The present invention concerns an electronic typewriter comprising an electric motor having a driveshaft which is rotatable in both directions, a first function device, a second function device, a shift member which is displaceable from one of two operative positions to the other to connect the first or the second function device to the driveshaft, a shift electromagnet for control of said shift member and an electronic control means for controlling the electric motor and the shift electromagnet.
French patent application No. FR-A-2 439 676 discloses a typewriter of that type in which the two devices comprise a line spacing device for rotating the platen roller and a transport device for moving a printing carriage in both directions in front of the platen roller. The electric motor rotates a driveshaft to which is fixed a single central drive wheel for the two devices, having two series of face teeth positioned on opposite sides. The line spacing and transport devices are motorized by means of two corresponding splined sleeves which are rotatable on the driveshaft, on the opposite side with respect to the drive wheel. The shift member comprises two wheels with face teeth, which are fixed in respect of rotation and which are axially slidable with respect to the two sleeves and which are capable of engaging with their face teeth with the teeth of the drive wheel. A power electromagnet, by means of lever systems, holds one of the two lateral wheels in engagement with the drive wheel and the other spaced from said wheel. An electronic control means controls the electromagnet for selection of one or other of the line spacing and transport devices, and controls the electric motor for selective rotation of the drive wheel and actuation of the selected device. That shift mechanism is rather complicated and expensive by virtue of the cost of the power electromagnet and the associated electronic control devices which are required for displacement of the wheels which can be coupled to the common tooth wheel.